advertisement


Too much oil in engine. A problem?

Mullardman

Mullardman

Moderately extreme...
Daughter has overfilled her Citroen DS3 DSport 1.6.

She got a warning message, not a light, on dash saying to top up oil. But..she had difficulty 'reading' the dipstick and has put about 1 litre of oil in for a top up. Now says she thinks it's reading 'a couple of Cm above full'. She's done several short journeys since without mishap or buzzers/bells going off, but since the owner manual insists on getting main dealer involved if oil level is above or below 'normal' she is panicking.

Does anyone have an informed view on whether this is a serious issue..which would mean me going over and trying to 'drop' a bit of oil from the sump, or is it safe to continue using the vehicle?

What, if any, detrimental effect, does 'a bit too much oil' have?
 
Easiest would be to find someone with a Pela pump; it's a suction pump which comes with a tube to stick down the dipstick tube.
 
If it is only a cm or two over max, no problem at all, especially on a petrol.
If you overfill a diesel sump you can get "diesel runaway" where enough of the overfilled oil gets up the bores to fuel the engine even with the throttle shut. It then runs at high speed on its sump oil and unless you are able to stall it it may self destruct.
Petrol is less of a problem. The worst case scenario, if heavily overfilled, is "windage" where the air that comes back down into the sump as the piston (s) descends has nowhere to go and blows the oil about. this causes oil foaming and can result in low oil pressure.
However for a cm or two, no problem. Service garages regularly do this to prolong the period before it needs a top up.
 
Probably OK at that ammount, but there are lots, and lots of YouTube videos, particularly on "Just Rolled In", showing problems with cars with too much oil added.

Not funny if this one is a problem, but "Just Rolled In" is amazing, shocking, mad, and very amusing, and not restricted to US video clips.
 
If she got a warning to top up, chances are the level was half a litre down on full, anyway, so she's probably only put half a litre more in than required, which is probably no more than 10% over capacity. Not a real biggie, I suspect. But might be an excuse to show her how to read the dipstick properly (ie the full 'wipe clean, then re-dip' routine) and also to allow a good minute or so for the new oil to percolate down to the sump and be measured, longer if cold.
 
This site contains affiliate links for which pink fish media may be compensated.
There would need to be a certain tolerance to over-filling due to the need to account for the times when the correct oil level is raised at front or rear of sump due to going uphill/downhill/cornering etc.

At a guess, in normal use at normal engine speeds, I doubt it will be a problem, even if the crank webs or conrod caps are making contact with the oil, I don't think it will be whipped up too much. Flat out at 6000RPM, maybe too much aeration, otherwise should be ok.

As said above, a request to top-up would mean at least 0,5l oil, so an extra 0,5l doesn't sound too onerous.

It may just be that she has measured the new level HOT instead of COLD. It will depend on what the owner's manual specifies.

Gut feeling - Low risk.
 
I wonder if overfilling is more common these days due to dipsticks on some cars being less easy to read clearly. The one on my old Mini was rubbish.
 
Very much depends on the amount of actual overfill.
I took an astra GTE in for service in the late 80's, picked it up, took it on my rounds of Cardiff / Newport from Brum, got a whiff of fire in the centre of Pontyprid, and some white smoke from the engine bay. Stopped, bonnet up, and there was the air filter blazing away.
Filter had filled with oil somehow from PCV, caught fire, and thankfully, a bus was driving by who had an extinguisher.

When I git it back from the garage in Cardiff, form said overfilled by 1.5 litres.
Took that to my main dealer who had done the service and we had a short, but expensive, (for them) conversation.
 
calorgas said:
I wonder if overfilling is more common these days due to dipsticks on some cars being less easy to read clearly. The one on my old Mini was rubbish.
Click to expand...
I wish my car HAD a dipstick. Instead it has some indicator on the dash that takes about 30 miles to work out when new oil has been added. Once again, automotive progress.
 
bor said:
There would need to be a certain tolerance to over-filling due to the need to account for the times when the correct oil level is raised at front or rear of sump due to going uphill/downhill/cornering etc.
.
Click to expand...
Oil surge is very definitely a problem in racing. That's why racing cars have dry sumps.
 
Get the biggest possible syringe from a pharmacy, put a couple of feet of plastic tube on it (the pharmacy might have that too, I don't want to know what for) and draw it out. I did it when I overfilled the gearbox on my motorbike.
 
Sonority said:
Very much depends on the amount of actual overfill.
I took an astra GTE in for service in the late 80's, picked it up, took it on my rounds of Cardiff / Newport from Brum, got a whiff of fire in the centre of Pontyprid, and some white smoke from the engine bay. Stopped, bonnet up, and there was the air filter blazing away.
Filter had filled with oil somehow from PCV, caught fire, and thankfully, a bus was driving by who had an extinguisher.

When I git it back from the garage in Cardiff, form said overfilled by 1.5 litres.
Took that to my main dealer who had done the service and we had a short, but expensive, (for them) conversation.
Click to expand...
That will be because some crankcase breathers vent to the air filter box, so any oil mist gets sucked into the engine and burnt off. Too much oil coming back that way could easily catch fire.
 
I wish my car HAD a dipstick. Instead it has some indicator on the dash that takes about 30 miles to work out when new oil has been added. Once again, automotive progress.
Click to expand...

Mine has a 'service' dipstick (a stubby little thing best accessed from below, on a ramp, ie during a service). The expectation is that the owner is never troubled by such things. I apparently get a dash warning if a top up is required, and the amount to add. Hasn't happened yet in the 7k miles I've done in the car. Hopefully this means the car isn't using much, if any, oil, not that the system is goosed.

I'd like a proper dipstick, if only to confirm it's the former, not the latter. Apparently, there's a 'police' dipstick option available for retrofit from Volvo. Might get that done at the next service.
 
stevec67 said:
I wish my car HAD a dipstick. Instead it has some indicator on the dash that takes about 30 miles to work out when new oil has been added. Once again, automotive progress.
Click to expand...
Yes, that is sheer madness! Sensors, indicators, LEDs and a few microchips and printed circuits with relative power supply to do what a steel stick can do. WHY?
 
I destroyed a Peugeot 405 diesel once by putting too much oil in. Electronic dipstick said 'no oil' so I obliged. The result a couple of miles down the road was nothing short of spectacular. Before the days of phones, but I would have filmed it as I walked away in the smoke :)
 
Suggest getting a second opinion on the actual oil level as currently revealed by the dipstick.

It seems unlikely that one litre would take it from under to 2cm over, but best to check, then fix. Because if a diesel is over-filled bad stuff may happen.
 
Nero said:
I destroyed a Peugeot 405 diesel once by putting too much oil in. Electronic dipstick said 'no oil' so I obliged. The result a couple of miles down the road was nothing short of spectacular. Before the days of phones, but I would have filmed it as I walked away in the smoke :)
Click to expand...
Yes, that's diesel runaway as I mentioned earlier. It is, as you say, spectacular.

Paul R said:
Suggest getting a second opinion on the actual oil level as currently revealed by the dipstick.

It seems unlikely that one litre would take it from under to 2cm over, but best to check, then fix. Because if a diesel is over-filled bad stuff may happen.
Click to expand...
Just looked again, does D sport mean diesel? If so then yes, I'd be going over to check.
Edit - there is a 1.6 petrol and a 1.6 diesel. It may be worth her getting the thing on level ground now it's settled down and checking it carefully before reporting back. I managed to do similar on a Jag diesel a couple of years ago, it was easy enough to pull the sump plug and drop off a litre or so before winding it back in. But as others have said, the "please fill" light was on and there is usually 1 litre from max to min, so it seems very unlikely that she has managed to significantly overfill it.
 
You must log in or register to reply here.


advertisement


Back
Top